Thermal Stress Analysis of the PCB Assembly Embedded in Polymer Potting Materials

Abstract

In this paper, extensive 3D thermal-stress finite element (FE) analyses were carried out for a potted system of printed circuit board assembly (PCBA). Considering the structural characteristics of solder-polymer interconnection, we adopted a homogenization method to obtain the homogenized property of the solder-underfill interconnection which can restore the stresses of solder and underfill ingredients. The hot spots in the board system for structural integrity due to thermal stresses were determined. The objective is to investigate the effects of material parameters on the thermal stress. Besides, typical potting materials were also examined to compare their thermal performances in order to guide the selection of potting materials.